1. Field of the Invention
The present invention relates to a probe having a tip (stylus) with a micro aperture for detecting or irradiating evanescent light and used in, e.g., a near-field optical microscope or the like, a near-field optical microscope, recording/reproduction apparatus, and exposure apparatus using the probe, and a method of manufacturing the probe.
2. Related Background Art
Recently, since the development of a scanning tunneling microscope (to be abbreviated as an "STM" hereinafter) that can directly observe the electron structure of surface atoms of a conductor (G. Binnig et al., Phys. Rev. Lett, 49, 57 (1982)) to allow high-resolution measurement of real space images irrespective of single crystal and amorphous, a scanning probe microscope (to be abbreviated as an "SPM" hereinafter) has been enthusiastically studied in the field of microstructural evaluation of materials.
As an SPM, a scanning tunneling microscope (STM), atomic force microscope (AFM), magnetic force microscope (MFM), and the like for detecting the surface structure using a tunneling current, atomic force, magnetic force, light, and the like obtained by bringing a probe with a micro tip close to a sample are known.
As one developed form of the STM, a scanning near-field optical microscope (to be abbreviated as an "SNOM" hereinafter) [Durig et al., J. Appl. Phys. 59, 3318 (1986)] for examining the sample surface by detecting evanescent light leaking out from a micro aperture at the sharp probe distal end using an optical probe from the sample surface has been developed.
Furthermore, a photon STM (to be abbreviated as a "PSTM" hereinafter) [Reddick et al., Phys. Rev. B39, 767 (1989)] as a one kind of SNOM for examining the sample surface by making light enter the sample rear surface via a prism under the total reflection condition, and detecting evanescent light leaking out through the sample surface using an optical probe from the sample surface has also been developed.
In the SNOM, since the distal end diameter of the optical probe determines resolution, the probe surface is shielded from light and a micro aperture is formed at the distal end to reduce the exit size of light. As a method of forming such micro aperture, the following method has been proposed. That is, a metal is coated on the intersection of the cleaved surfaces of a transparent crystal, and the crystal is pressed against a hard surface to remove the metal at the intersection portion and expose the intersection, thus forming a micro aperture (see FIG. 14A) (European Patent No. EP0112402). In another method, the distal end of an optical fiber is sharpened by etching, and a metal is evaporated on the optical fiber from only a given direction while rotating the fiber so as to form a portion on which no metal is evaporated, thereby forming a micro aperture (see FIG. 14B).
However, of the above-mentioned prior arts, when the optical probe has no micro aperture like in the PSTM, stray light other than evanescent light such as light scattered by the three-dimensional pattern on the sample surface is detected, thus dropping the resolution.
On the other hand, the prior arts shown in FIGS. 14A and 14B have poor productivity and can hardly attain integration and size reduction of the micro aperture since they present micro aperture formation processes for only one fiber probe. Also, high cost is required due to complicated, time-consuming processes. Furthermore, it is hard to strictly control the diameter of the micro aperture, resulting in poor reproducibility. If an EB working apparatus or FIB working apparatus is used, formation of an aperture with a diameter of 100 nm or less may be realized in principle. However, positioning control of such apparatus is complicated, and variations are readily produced. Moreover, since such working method must be done for each point, the yield is poor.